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Rodents are considered good models for investigating genotoxic damage and mutagenic alterations caused by xenobiotic agents, due to their occupation of a wide variety of habitats. However, relatively few in situ studies have focused on DNA damage in wild rodents associated with environmental exposure. In this review, we investigate trends in the application of the micronucleus test and comet assay in in situ studies of wild rodents. A total of 33 papers were identified, distributed across 14 different countries. Brazil and Spain had the most published studies (six each), followed by Bulgaria (n = 5), Mexico (n = 4) and Italy (n = 3). Only 24 of the 2,652 recognized rodent species have been the subject of in situ studies, which have most frequently focus on species of the genus Mus. The protocols used for the micronucleus test and comet assay varied widely, although blood and bone marrow were the primary types of tissue used. Given the paucity of studies on wild rodents, we recommend further research, particularly focusing on the use of this group as bioindicators of environmental quality and the standardization of protocols.

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The field study aims to address identified research gaps by providing valuable information on the concentration, spatial distribution, pollution levels, and source apportionment of toxic and essential elements in sediment samples from four sampling sites (P1: Beira Rio (urban area), P2: Bananal (rural area), P3: Embiral (rural area), P4: Cidelândia (rural area) distributed along the middle Tocantins River, Brazil. Samples were collected in 2023 from river sections and analyzed using various contamination índices (geoaccumulation index, contamination factor, enrichment factor, pollution load index, sediment pollution index, potential ecological risk coefficients, and integrated risk index). Results indicated that the levels of aluminum, iron, manganese, and selenium exceeded legal standards in that year. Chromium, nickel, copper, zinc, and lead exceeded guidelines, mainly in section P1 for aluminum and section P3 for nickel and lead. Rainy months showed increased presence, indicating seasonal variability. The geoaccumulation index indicated low pollution levels, with lead and nickel notably present near urban and industrial areas. The enrichment factor highlighted elevated concentrations of lead and zinc in industrial areas. Both PLI and SPI indices raise concerns regarding Pb (P4) and Zn (P3) concentrations at specific times of the year. Overall, potential ecological risks were deemed low for most sites. Continuous monitoring and interventions are crucial to preserve water and environmental quality in the region.

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The increase in the world population and the intensification of agricultural practices have resulted in the release of several contaminants into the environment, especially pesticides and heavy metals. This article reviews recent advances in using adsorbent and catalytic materials for environmental decontamination. Different materials, including clays, carbonaceous, metallic, polymeric, and hybrid materials, are evaluated for their effectiveness in pollutant removal. Adsorption is an effective technique due to its low cost, operational simplicity, and possibility of adsorbent regeneration. Catalytic processes, especially those using metallic nanoparticles, offer high efficiency in degrading complex pesticides. Combining these technologies can enhance the efficiency of remediation processes, promoting a more sustainable and practical approach to mitigate the impacts of pesticides and other agricultural pollutants on the environment. Therefore, this review article aims to present several types of materials used as adsorbents and catalysts for decontaminating ecosystems affected by agricultural pollutants. It discusses recent works in literature and future perspectives on using these materials in environmental remediation. Additionally, it explores the possibilities of using green chemistry principles in producing sustainable materials and using agro-industrial waste as precursors of new materials to remove contaminants from the environment.

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Phytoremediation is a useful, low-cost, and environmentally friendly alternative for the rehabilitation of heavy-metal-contaminated (HM) soils. This technology takes advantage of the ability of certain plant species to accumulate HMs in their tissues. Crotalaria pumila is a herbaceous plant with a wide geographical distribution that grows naturally in environments polluted with HMs. In this work, the bioaccumulation capacity of roots and leaves in relation to five HMs (Cr, Cu, Fe, Pb, and Zn) was evaluated, as well as the morphological changes presented in C. pumila growing in control substrate (without HMs) and mine-tailing substrate (with HMs) under greenhouse conditions for 150 days. Four metals with the following concentration pattern were detected in both tissues and substrates: Fe > Pb > Cu > Zn. Fe, Pb, and Zn concentrations were significantly higher in the roots and leaves of individuals growing on mine-tailing substrate compared to the control substrate. In contrast, Cu concentration increased over time in the exposed individuals. The bioconcentration factor showed a similar pattern in root and leaf: Cu > Fe > Pb > Zn. Around 87.5% of the morphological characters evaluated in this species decreased significantly in individuals exposed to HMs. The bioconcentration factor shows that C. pumila is efficient at absorbing Cu, Fe, and Pb from the mine-tailing substrate, in the root and leaf tissue, and the translocation factor shows its efficiency in translocating Cu from the roots to the leaves. Therefore, C. pumila may be considered as a HM accumulator plant with potential for phytoremediation of polluted soils with Cu, Pb, and Fe, along with the ability to establish itself naturally in contaminated environments, without affecting its germination rates. Also, it exhibits wide geographical distribution, it has a short life cycle, exhibits rapid growth, and can retain the mine-tailing substrate, extracting HMs in a short time.

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The Tocantins-Araguaia basin is one of South America's largest river systems, across three Brazilian states (Maranhão, Tocantins, and Pará), within the Legal Amazon region. Despite draining extensive Cerrado savanna and rainforest ecosystems, it has suffered significant degradation, notably in the past 40 years. Human activities, including agricultural expansion, deforestation, and the introduction of non-native species, have worsened the environmental damage, which is alarming since many residents and villages along the middle Tocantins River rely on it for water supply, recreation, and fishing. This study assessed the concentration of potentially toxic and essential elements in water samples from four sampling sites distributed along the middle Tocantins River. The monitoring occurred throughout 2023, involving the measurement of parameters both on-site and in the laboratory. Water quality and its health implications were evaluated using the Weighted Arithmetic Water Quality Index (WAWQI), the Water Quality Index (WQI), and the health risk assessment index. The levels of aluminum, copper, iron, magnesium, and selenium exceeded legal standards. Seasonal fluctuations indicate a complex dynamic influenced by climatic or seasonal factors, with February showing the highest values. Site P1, located in urban areas, exhibited elevated mean concentrations for conductivity, total dissolved solids (TDS), and chlorophyll, indicating the need for continuous monitoring. The nitrogen concentrations at P1 raise concerns regarding drinking water quality, which is a concern for the region's residents who use untreated river water. Despite seasonal variations in element concentrations, the overall WAWQI categorized all sections as "Excellent," and the WQI rated as "Good." Human health risk assessments detected no risks, but continuous monitoring and interventions are crucial for sustained water quality improvement.

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The Fundão dam collapse was one of the largest mining-related disasters globally. It resulted in the release of mining tailings containing heavy metals, which contaminated the Doce River in southeastern Brazil. This study assessed the effects of acute exposure of Danio rerio embryos to sediments contaminated by mine tailings six years after the Fundão dam collapse. The study sites included P2, P3, and P4 in the upper Doce River, as well as site P1 on the Piranga River, an uncontaminated river. Sediment samples were analyzed for 10 metals/metalloid by atomic absorption spectrometry. In the assays, embryos were exposed to sediment from P1-P4 sites, and uncontaminated quartz was used as control sediment. Various biomarkers were applied to assess biological responses, and the integrated biomarker response (IBR) index was calculated for each site. Sediment samples revealed elevated levels of As, Cr, Cu, Hg, and Ni beyond Brazilian legislation limits. At 96-h exposure, embryo mortality rates exceeded 20% in P1, P2, and P3, higher than the control and P4 (p < 0.0001). Hatching rates ranged from 60 to 80% in P1, P2, and P3, lower than the control and P4 (p < 0.001). Larvae exposed to P2 sediment (closest to the Fundão dam) exhibited skeletal, physiological, and sensory malformations. Neurotoxicity was indicated by increased acetylcholinesterase activity and reduced spontaneous movements in embryos exposed to Doce River sediment. Contamination also increased metallothionein and heat shock protein 70 levels, along with changes in cell proliferation and apoptosis. Principal component analysis showed a good correlation between metals/metalloid in the sediment and larval morphometric endpoints. The IBR index highlighted suitable biomarkers for monitoring metal contamination in fish embryos. Overall, our findings suggest that sediment toxicity following the Fundão dam failure may compromise the sustainability of fish communities in the Doce River.

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Heavy metal pollution in soil has emerged as a major environmental concern. This can be attributed to human activities such as mining, modern agriculture, and industrialization. This study was conducted to determine how heavy metals spread from mine tailings to surrounding farmland. Metal absorption and accumulation were also investigated in the root and shoot biomass of tapioca crops grown in those farmlands. Metal concentrations in MTAS1 were 85.3 ± 1.2, 45.8 ± 1.5, 134.8 ± 1.7, 92.4 ± 2.2, and 78.95 ± 1.4 mg kg-1, respectively. Heavy metal concentrations in MTAS2 and MTAS3 were found to be 79.62 ± 1.6, 75.4 ± 1.5, 41.31 ± 1.1, 47.8 ± 1.6, 142.5 ± 2.1, 128.4 ± 1.4, 86.2 ± 1.9, 79.5 ± 1.3, and 83.4 ± 1.2 mg kg-1, respectively. Tapioca crop shoot and root biomass grown at these metal polluted sites absorbed and accumulated significant amounts of Cd, Cu, Zn, Pb, Ni, and Mn. Notably, the metal content of the tapioca crop's root and shoot biomass exceeded national standards.

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INTRODUCTION: Lead poisoning in childhood remains an important public health concern. We highlight the radiological findings in a patient with a high blood lead concentration. CASE SUMMARY: A 7-year-old girl presented to hospital with abdominal pain, nausea, and asthenia. Laboratory tests showed severe hypochromic microcytic anemia, punctate basophilic stippling of erythrocytes, and a blood lead concentration of 880 µg/L (4.3 µmol/L). IMAGES: Radiographs of the femur, tibia, and fibula demonstrated dense metaphyseal bands ("lead lines"). On cranial computed tomography, we observed multiple speck-like and curvilinear hyperdensities involving subcortical regions, putamen, and left cerebellar hemisphere. CONCLUSION: In patients with lead poisoning, imaging of the brain and bones may show characteristic features. These imaging findings may point to the diagnosis of lead toxicity when these radiographic findings are discovered during the evaluation of vague complaints such as abdominal pain or mental status changes or when a blood lead concentration is not readily available.

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Introduction: Electronic nicotine delivery systems (ENDS) are gradually becoming more popular, particularly, among today's youth. Despite being marketed as safe by the tobacco industry, the notable absence of regulation in their composition is evident. Both the generated fluids and aerosol exhibit a wide variety of substances that are not yet fully identified. In addition to additives, the aerosol contains metals, the presence of which can be attributed to the excessive heating of metallic filaments used in vaporizing the liquid. Objective: This review aimed to identify and describe studies that have assessed metal levels in biological samples obtained from electronic cigarette users and those exposed to their second-hand aerosol. This involved detailing the types and concentrations of metals identified and the biological samples in which the metals were detected. Methods: Two independent researchers conducted searches in the MEDLINE and EMBASE databases to identify studies that measured the metal levels in human non-invasive biological samples from electronic cigarette users and second-hand exposure. Data were presented as a narrative review. Results: In total, 18 articles were included in this review. Overall active and passive exposure to ENDS was related to higher levels of many metals, including lead and cadmium, in biological samples. ENDS users, in general, have lower metal concentrations in biological samples compared to the users of combustible cigarettes. Conclusion: The exposure to primary and second-hand e-cigarette aerosol is related to higher metal concentrations in the biological samples. The adverse effects of this exposure on long-term users are yet to be determined.